Flow meter with cylindrical spring restriction



April 18, 1961 L. E. MAIN ETAL 2,979,947

FLOW METER WITH CYLINDRICAL SPRING RESTRICTION Ik #lit/ans.

April 18, 1961 E. MAIN ETAL FLow METER WITH CYLINDRICAL SPRINGRESTRICTION Filed Jan. 14, 1958 3 Sheets-Sheet 2 Wim Nl April 18 1961 L.E. MAIN ETAL 2,979,947

FLOW METER WITH CYLINDRICAL SPRING RESTRICTION Filed Jan. 14, 1958 3Sheets-Sheet 25v l l al r l l I ff f@ ZZ @f M 12 @gi/QS.

nited States Patent FLOW METER WITH CYLINDRICAL SPRING RESTRICTION LeoE. Main, Chicago, Jack R. Piper, Mount Prospect, and Lawrence J. Smith,Oak Park, Ill., assignors to -Bell & Gossett Company, Oak Park, Ill., acorporation of VIllinois Filed Jau. 14, 195s, ser. No. 703,933

1o claims. (c1. 'I3-201) This application is tiled as acontinuation-in-part of our copending application, Serial No. 517,852,filed June 24, 1955, now Patent No. 2,850,897, the disclosure of which,to the extent it is not inconsistent herewith, is specificallyincorporated by reference. v a

Our invention relates to a fluid flow meter capable of easy insertion ina pipe or conduit and arranged to visually indicate the presence andrate ofow therethrough as well as the temperature of the iluid, whetherliquid or gas.

Meters of this type are particularly useful in parallel branch circuitswhich receive their iluid from a common supply pipe where it is desiredto establish different ilow rates in the several circuits. VThey havespecial application in the multi-circuit type of hot water heatingsystem where the heat load in one circuit may differ from that inanother circuit. Assuming a two-circuit system by way of example, it ispossible to establish visually observable, different ow rates in the twocircuits based upon the calculated heat requirements thereof. Thisprocedure enables the meters to be installed at any time of the yearrather than only during the heating season. v

S far as known, such meters generally include a movable member which isbiased towards av zero position by a spring and whose position at anyinstant is determined by the fluid ow rate through the meter, the memberbeing exposed to the iluid flow.

It is therefore one object of our invention to provide a flow meter inwhich the indicating member that is responsive to and indicates ilowrate takes the form of an extendible, conical, helical spring whosedeflection curve is parabolic or linear depending upon other factors inthe meter, or of a simple helical spring characterized by a linear,deection, or `of a conical, helical spring which shortens in length fordifferent llow rates and exhibits a linear deflection curve.

A further object is to provide a ow meter which incorporates a controlvalve whose adjustment determines the ow rate visually indicated byother parts of the meter to thereby eliminate the necessity for acontrol valve elsewhere in the associated pipe.

A further object is the provision of a ow meter having any of theresponsive members above which is housed for movement within atransparent tube carried by a substantial structure having sufficientrigidity to enable the application of a wrench thereto for mounting themeter in a pipeline without damage to o'r requiring theremoval of 'thetransparent tube.

These and further objectsl of the invention will be set forth in thefollowing specification, referencelbeing had to the accompanyingdrawings, and the novel means by which the objects are etfectuated willbe denitely pointed'lout in the claims.

In the drawings:

Fig. lisa fragmentary elevation Vshowing-thc'sapplica-A tion of 1thevflow meter. tor parallel circuitsf'in 'f a v`hot' waterheatingfsystemn 'f 2,919,947 Patented Aw'p'l". Y18,v

ice

. 2 Fig. 2 is an enlarged, sectional elevation of the meter taken alongrthe longitudinalaxis thereof. a .l

Figs. 3, 4 and 5 are sections along the lines 3 3, 4 4, and 5-5,respectively, inFig. 2. ,Y Fig.r 6 is a fragmentary section as in Fig. 2diagramrnatically showing the indicating spring elongated in response tosome ow rate. Figs. 7, 8 and 9 are fragmentary sections similar to Fig.6, but showing modified arrangements.

Figs. 10 and 1l .are views of the upstream and downstream ends,respectively, of the skeleton carrier of the invention. Y Y Referring toFig. 1, the vnumeral, 10 designates a typical hot water boiler vformingpart of a hot water heating system whose heating units (not shown)l aresupplied through a pipe 11 thatl may include the usual flow controlkvalve 12. Water from thenheatin'g units `returnsto .the boiler througha pipe 13 which preferably includes a motor operated pump 14 forestablishing forced circulation through the system whenever demanded bya room thermostat (not shown). y g Y a The system shown is of themulti-circuit type, two such circuits being indicated which are servicedby the parallel pipes 15` and 16, respectively, thatare bridged betweenthe supply and return pipes 11 and 173 respectively. If it be assumedthat the heatprequirements in the two circuits differ, it is importantfor etlicient operation that the liquid ow rates through the pipes 15and 16 be ladjusted accordingly and, for this purpose, a flow meter 17is incorporated in each of the latter `pipes and illustrated moreparticularly in Figs. 2-6, inclusive. Referring to Fig'. 2, the'numerals 18 and 19 designate coupler blocks which are positionedatopposite ends, respectively, of the meter and axially threaded toreceive ends o-f sections comprising the pipes 15er 16 of Fig. 1. Thedetailed illustration of Fig. 2 is shown in relation to the Ipipes 15.These blocks are preferably hexagonal in transverse section and areconnected by facing, semif hexagonal, metallic shells 20 and21 which are,firmly attached to the blocks 18 and 19 in any approved manner. Theportions of the shells which overlie the blocks providewrench-'receiving surfaces and the structure has Sru'icient rigidity toenable the meter to be installed in a pipeline without removing orendangering the transparent tube presently described'. y

This tube, indicated by the numeral 22, may be composed of glass orgenerally any material, characterized by adequate transparency and ismounted coaxial with, audits opposite ends are supported in, the couplerblocks 18 and 19, respectively. Specifically, the block 18, which is theinlet end of the meter 17, includes a passage 23 coaxial with andproviding communication between one section of the pipe 15 and the inletend of the tube 22,

cessively interposed between the shoulder 25 andilange` 26 and alsoencircling the tube 22 is a packing ring 27 and a sleeve 2S which has aloose fit on the tube. Cap,

screws Z9 extend through the ends of the ilange 26 aridl arethreaded inthe coupler block 18 to thereby provide'f a means for moving the iiange26 towards thel left, as

viewed in Fig. 1, and effecting a leak-tight contactof' the packing ring27 with the tube 22, wall 24 and shoulder 25, andalso providing acushioned support for the latter tube. f

Consideringftheoppositeend of the meter 17,A coupler block 19`Jincludesa passage V30 coaxial ,vvithgandv providing communication between' theother' section of the pipe and the delivery end of the tube 22. TheVinlet end of the passage merges with a counterbored portion in the block19 including an annular wall 31 having a larger diameter than theoutside diameter of the tube 22 and an annular shoulder 32. The axiallength of the wall 3l is longer than that of the wall 24 for a purposepresently explained.

A spacer sleeve 33 lits easily within the annular wall V31 with one endabutting the shoulder 32 and its inner `*diameter is such that it hasloose guiding relation to the adjacent end of the tube 22 which extendsslightly within the vsleeve 33 as shown when the meter is conditionedfor service. Abutting the opposite end of the spacer sleeve v33 is apacking ring 34 which is expanded into leak-tight connection with thetube 22, wall 31 and sleeve 33 by a pressure set up by cap screws 35threaded in the block 19 and acting successively through an elongatedflange 36 and sleeve 37, the latter ange and sleeve loosely encirclingthe tube 22. The shape of the flange 36 is shown in Fig. 3 and the ange26 is identical. The packing ring 34 also provides a cushion support forthe adjacent end of the tube 22.

To visually indicate the flow rate as well as the teiperature of liquidflowing through the tube 22, the following instrumentalities areprovided. A skeleton carrier 38 of light weight is positioned within thetube 22 and is conditioned to neither exercise any substantialrestriction on nor to create any turbulence in the liquid ow.Specifically, the carrier 38 includes a thin, at plate 39 (see the endview thereof in Fig. 10) diametral- 'ly positioned within the tube 22adiacent the inlet end thereof and from which extend oppositely directedarms 40-40, each of which terminates in an ear 41 interposed between theshoulder 25 and the end of the tube 22 to thereby anchor the carrier 38against endwise displacement in the direction of liouid flow. A likeplate 42 (see the end view thereof in Fig. ll) is located at theopposite end of the carrier 38 short of the delivery end of the tube 22and in coplanar relation to the plate 39, the plates 39 and 42 beingconnected by a neck 43 (see Fig. 3) which joins the upper portions Vofthese plates so that there is clear space below the neck 43 and betweenthe plates as viewed in Fig. 2. The plate 42 is supported in the tube 22by legs 42a.

The plates 39 and 42 constitute spaced apart centering structures, thelegs of which present surfaces for engagement with the inner peripheryof the conduit for locating these structures against transverse movementin the conduit. These centering structures support the guide wire at itsopposite ends to locate the guide wire substantially medially in theconduit. While in the preferred form disclosed herein the guide wire isa relatively weak member and the neck 43 is relied upon for lending thenecessary rigidity to the skeleton carrier, the guide element may bemade of a strength sufficient to eliminate the necessity of the neck.

' A conical, helical spring 44 formed of wire is positoned within and sothat its axis extends longitudinally of the tube 22. The maior end ofthe spring 44 lies adjacent the carrier plate 39 and the wire composingthis end of the spring is extended at 45 for anchorage attachment tothis plate. The opposite or minor end of the '4 weight and accordinglyvery responsive to liquid impact. In Fig. 2, the spring is shown in abiased, non-elongated position in which the convolutions are in touchingrelation or substantially so, corresponding to either an absence of flowthrough the meter, or a flow so minute as not to be measurable by aninstrument of this type. When the spring is elongated, the smallestconvolution thereof 1s guided by a vwire 48 which extends generallycoaxially through the spring and is bridged between the carrier plates39 and 4-2, the diameter of the guide wire 48 being such that thevsmallest convolution of the spring 44 will move freely therealong. y yAlso lbridged between the carrier plates 39 and 42, and at the sameelevation as, and close to the neck 43 1s a thermometer49 for visuallyindicating liquid temperature with reference to atherinometric scale 50arranged as a transparent decal affixed to the outer surface of the tube22. Since the scales 47 and S0 would be affixed to the right half of thetube 22, as viewed in Iig. 3 and so actually would not appear in theFig. 2 section, they are for`convenience shown by dot and dash lines inthe `latter figureto delineate their relation to the indicator 46 andthermometer 49. For ready viewing of the two latter elements, the shells20 and 21 on their right sides, as viewed in Fig. 3, are cut awaybetween the blocks 18 and 19 to provide complementarily related opemngs51 and `52, respectively, which together form one elongated openingpermitting observation of the tube 22 between the flanges 26 and 36. Theopposite sides of the shells 20 and 21 are also cut away to provide likeopenings 53 and 54, respectively, which are interrupted by a central webwhose transverse edges are spaced conveniently from the flanges 26 and36, respectively.

Any selected liow rate through the meter 17 is established by a controlvalve 56 of the butterfly type which is positioned in the deliverypassage 30 and affixed toV the lower end of a stem 57 which is rockablymounted in the coupler block 19 and extends externally thereof forworking connection with a suitable tool. Leakage along the stem 57 isprevented by a packing-smiling box structure, generally indicated by thenumeral 58.

When ow is established through the meter 17 by opening the valve 56fully or partially, the spring 44 will elongate a distance proportionalto the ow rate due to the liquid impact and by observing the position ofthe indicator 46 relative to a marking on the flow rate scale 47, thisrate can be determined. In this connection, it will be noted that therate scale 47 is calibrated on any desired volumetric rate basis, suchas gallons per minute, and since the deflections of the spring 44 forvarying flow rates follow a parabolic pattern, the markings on the scale47 are accordingly spaced as shown. The spring 44 is highly sensitive tochanges in ow rate, any particular rate being established byappropriately posit1oning the valve 56.

The meter 17 is characterized by ruggedness and by simplicity instructure that is reflected in manufacturing economies, particularlywith reference to assembly. For

. example, the transparent tube 22 and the parts housed spring 44 isfree to move and the smallest convolution is transversely extended to aconvenient diameter to provide an indicator or annular finger 46. Whenthe spring 44 is elongated by the liquid flow, the indicator 46 movesrelative to a transparent decal scale 47 which is affixed to the outersurface of the tube 22 and appropriately calibrated to indicate flowrate for any position of the indicator.

For a sample unit, the spring 44 may be composed of wire having adiameter of .016" and its non-extended length, as shown in Fig. 2,- is9%", the diameter of the large end of the spring being 1%2 while that`of the small end The spring w44 isuthereforenlight in;-

therein may be subassembled and this collection installed as a unit inthe coupler blocks 18 and 19. To remove this subassembly, it is merelynecessary to withdraw the cap screws 29 and 35, slide the tube 22towards the right in Fig. 2 and the sleeves 28, 33 and 37, the flanges26 and 36, and the packing ring 34 towards the center of the tube 22,whereupon the left end of the tube 22 may be swung through the openingformed by the cut-outs 51 and 52.

In Figs. 7 to 9, inclusive, are illustrated varying meteringarrangements in which some of the elements are identical with thoseheretofore described and are designated by the same numerals.

Referring to Fig. 7, the metering spring 44 is also used,

l but an additional .element is lintroduced which renders' the springmore sensitive t0 A$.0-ta11ed low ows, i.e., ows

up to about 3% gallons per minute, all rate' figures assuming that theliquid lis water or a liquid having about the same viscosity. This addedelement ta'kes the form of an oriiice 59 which, referring to Fig. 2,wouldl be positioned in the passage 23 with its delivery end coaxial'with the spring 44 and having a diameter such that liquid issuing fromthe orice is directed to the interior of the spring.

The orifice 59 is shaped so that the velocity of the liquid directed tothe interior of the spring 44 is higher than if the orifice were notpresent.A Accordingly, the kinetic energy of each unit volume of theliowing liquid is higher and hence its impact effect. If the tube 22 beconsidered as filled with a liquidrwith the valve closed and a constantpressure head acting at the inlet of the oriice 59, the spring 44 isthen in the retracted or closed position as shown in Fig. 2. In thiscondition, the spring 44 has the form of a conical, hollow shell whoseonly opening at the small end is that provided by the smallestconvolution of the spring, which is negligible. This spring shell isfilled with the liquid in a static condition and when the valve 56 isopened to the desired extent, the liquid issuing from the Aorificeexerts a `directed pressure on the incompressible liquid mass within thespring shell so that the spring begins to elongate. When theconvo1utions have opened suiiiciently, the original liquid mass withinthe spring shell is gradually replaced by the continuing ow which yalsoacts against the surfaces on the uncovered convolutions. Deliections ofthe spring 44 in this modification are linear, and the markings on thellow rate scale 47 are arranged accordingly. The above springv actionalso occurs in the Fig. 2 modilicatin, but the annular liquid massoutwardly of the spring plays little or no part in the springelongation, but this fact is unimportant because of the higher flowrate.

In Fig. 8, the helical metering spring 60 is of the cylindrical type andcarries an indicating disk 61 on its free end which is subject to flowimpact. The deflection curve of this spring is parabolic. The indicatordisk 61 may also be used with the spring 44 in Fig. 2.

It will be apparent that the spring 60 of theFig. 8 arrangement may beof the tension type as in the case of spring 44 of Figs. 6 and 7, inwhich case liquid ow is from left to right in Fig. 8 and the spring isshown in an extended flow-rate indicating position, or the spring 60 maybe of the compression type, in which case liquid ilow must be from rightto left in Fig. 8, and it will be understood that in the case of acompression spring the illustrated position thereof in Fig. 8corresponds to a zero ow rate. Y I

Whether considering the spring arrangement of Fig. 8 as a tension orcompression type, liquid How through the tube 22 exerts pressure on theupstream face of the disk 61 for loading the spring and thereby changingthe length thereof to produce the desired indication of the iiow rate. l

In Fig. 9, the conical, helical spring 62 is of the compression type andis shown in fully elongated position corresponding to an absence of flowthrough the tube 22. The large end of the spring 62 is backed by aspider 63 which is retained in position by a sleeve 64 suitably held inthe tube, while the small and free end of the spring carries anindicating disk 65 exposed for liquid impact. This disk is guided formovement on a wire 66 which extends therethrough, one end of the wire 66being attached to a retainer 67 at the inlet end of the tube 22 and theopposite end being supported by the spider 63.

Liquid iiowing through the tube 22 exerts pressure on the disk 65 andeilects a compression of the spring 62, f

components of the pressure also acting against the flaring side of thespring. The extent of the compression depends upon the ow rate up to amaximum in which the spring assumes a substantially flattened conditiondue to the nesting of successive convolutions. The deflection curve ofthis spring is linear.

'asusta *Y l. Y 6 VWhile the flow meter is specitically shown in thedrawings as applied to a liquid system and so described,.it is alsocapable of use in any gas system.

l. In a fluid flow meter including a conduit arranged forinterposition'in a pipe line and having an inlet end, an outlet end, anda transparent section therebetween, a. unit assembly for indicating theliow rate of fluid in said conduit and comprising a skeleton lcarrierpositioned in the conduit and held against movement therealong andincluding spaced apart centering structures each having surfacesextending to and engageable with the inner` periphery of said conduit ata plurality of points spaced thereabout for locating said structuresagainst transverse movement in said conduit, an elongated guide elementhaving its opposite ends supported in said structures to locate saidelement substantially medially in said conduit, a cylindrical helicalspring in telescoping relation with said guide element and extendingendwise thereof forA exposure to fluid iiow in said conduit, one end ofthe'spring being anchored to one of said structures and the other endbeing confined against transverse movement in the conduit by engagementwith said guide element, said en# gagement accommodating free-slidingmovement between said other end and said guide element in a directionendwise of the conduit such that said other end is an indicator relativeto visible indicia associated with the transparent section. p

2. The arrangement of claim l wherein said guide element is a wire andsaid spring is telescoped over the wire.

3. The arrangement ofaclaim 1 wherein said centering structures areinterconnected by a neck portion extending therebetween to maintain thespacing thereof, said guide element is a wire, and said spring istelescoped over the` Wire.

4. The arrangement of claim l wherein said skeleton carrier has meansthereon facing downstream for abutting engagement with anupstream-facing surface of said conduit to maintain said carrier againstdown-stream movement through said conduit.

5. The arrangement of claim 4 whereinA said downstream-facing means iscarried by the upstream one of said structures.

6. A fluid ow meter comprising an elongated shell member having apassaged block at each end for receiving a pipe section,l a transparenttube providing a ow` connection between the blocks and having leaketightcon-r nections therewith, a skeleton carrier positioned in the tube andheld against movement therealong including. al pair of spaced, fiat,tnin plates located within and ad-u jacent theY inlet and outlet of thetube, respectively, and positioned lengthwise thereof, the inlet andoutlet plates, respectively, including arms having anchoring engage-`ment with the inlet end of the transparent tube and supporting contactwith the inner wall of the transparent tube, a guide wire securablybridged between the plates, and means for indicating the fluid flow ratethrough the tube including a cylindrical helical spring exposed to thefluid flow and extending longitudinally of the tube around the guidewire, one end of the spring being anchored tothe flat plate adjacent thetube inlet and the other end being free to move along the guide wire asan indicator relative to a scale on the transparent tube.

7. A fluid flow meter comprising an elongated housing having a passagedblock at each end thereof for receiving pipe sections, a transparenttube providing a flow connectionbetween the blocks and having leaktightconnections therewith, a skeleton carrier positioned in the tube andheld against movement therealong including spaced apart centeringstructures each having surfaces extending to and engageable with theinner periphery of said tube at a plurality of points spaced thereaboutfor locating said structures against transverse movement in said tube,an elongated guide element having its opposite ends supported in saidstructures to l0- cate said element substantially medially in said tube,a cylindrical helical spring in telescoping relation with said guideelement and extending endwise thereof for exposure to uid ow in saidtube, one end of the spring being anchored to one of said structures andthe other end being conned against transverse movement in the tube byengagement with said guide element, said engagement accommodatingfree-sliding movement between said other end and said guide, element ina direction endwise of the tube such that said other end is an indicatorrelative to visible indicia associated with the transparent section.

8. A uid flow meter comprising an elongated shell member including acut-out portion delining an observing window and having a passaged blockat each end for receiving a pipe section, a transparent tube bridgedbetween the blocks and viewable through the window, the opposite ends ofthe tube being received within relatively long and short counterbores inthe blocks, respectively, and the tube being normally positioned withone end spaced from the shouldered end of the long counterbore and theother end adjacent the shouldered end of the shortA counterbore,detachable packing means surrounding each end of the tube within eachcounterbore, a skeleton carrier positioned in the tube and held againstmovement therealong including a pair of spaced, at, thin plates locatedwithin and adjacent the inlet and outlet of the tube, respectively, andpositioned lengthwise there- 0f, the inlet and outlet plates,respectively, including arms having anchoring engagement with the inletend of the transparent tube and supporting contact with the inner wallof the transparent tube, a guide Wire securably bridged between theplates, and means for indicating the uid flow rate through the tubeincluding a cy` lindrical helical spring exposed to the fluid flow andextending longitudinally ot the tube around the guide wire, one end ofthe spring being anchored to the flat plate adjacent the tube inlet andthe other end being free to move along the wire as an indicator relativeto a scale on the transparent tube, the relative lengths of the windowand tube being such that when the packing means are detached and movedto a position central of the tube, the latter is movable endwise toclear the short counterbore for removal thereof and the enclosed carrierthrough the window.

9. A fluid flow meter comprising an elongated housing having a cut-outportion dening an observing window and having a passaged block at eachend for receiving a pipe section, a transparent tube bridged between theblocks and viewable through the window, the opposite ends of the tubebeing received within relatively long and short counterbores in theblocks, respectively, and the tube being normally positioned with oneend spaced from the shouldered end of the long counterbore and the.other end adjacent the shouldered end of the short counterbore,detachable packing means surrounding each end of the tube within eachcounterbore, a skeleton carrier positioned in the tube and yheld againstmovement therealong and including spaced apart centering structures eachhaving surfaces extending -to and engageable with the inner periphery ofsaid tube at a plurality of points spaced thereabout for locating saidstructures against transverse movement in said tube, an elongated guideelement having its opposite ends supported in said structures to locatesaid element substantially medially n said tube, a cylindrical helicalspring in telescoping relation with said guide element andrextendingendwise thereof for exposure to fluid flow in said tube, one end of thespring being anchored to one of saidrstructures and the other end beingconfined against transverse movement in the tube by engagement with saidguide element, said engagementY accommodating free-sliding movementbetween said other end and said guide element in a direction endwise ofthe tube such that said other end is an indicator relative to visibleindicia associated with the transparent section.

10. A skeleton carrierfor mounting in a uid flow conduit to anchor andguide an extensible coil spring within said conduit, said carriercomprising a one piece skeleton frame having lengthwise spaced centeringstructures interconnected by a lengthwise extending integral neckportion for supportingy and maintaining the centering structures inpredetermined spaced relation along the conduit, each centeringstructure comprising a plate ori ented in a plane lengthwise of saidcarrier to present a minimum flow restriction in said tube and aplurality of integral legs projecting from said plate in directionstransverse of said carrier for engagement interiorly with said conduitfor positioning the structures against transverse movement, one of saidplates having formations for an choring one end of said spring againstdownstream movement and one of said plates having formations at theextremities of the legs thereof for anchoring engagement with theconduit to prevent downstream movement of the carrier, with said neckportion extending between corresponding transverse extremities of saidplates, and an elongated wire-like guide element for receiving thespring in telescoping relation and having its opposite ends connected tosaid plates substantially medially thereof to extended in parallelspaced relation to said neck portion.-

References Cited in the tile of this patent UNITED STATES PATENTS2,311,375 Farwick Feb. 16, 1943 2,313,889 Porter Mar. 16, 1943 2,850,897Main et al Sept. 9, 1958

